1. Click "Start"

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2. Click "Settings"

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3. Click "Windows Update"

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4. Click "Check for updates" and update all pending updates and restart your machine 

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5. After PC restart Click "Start" then click "Settings" then click "System" then click "Activation"

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6. Then click "Change" at the Change product key and enter the key and click next and follow the prompt and restart your machine again

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